title: An observational study of the effectiveness and safety of natalizumab in the treatment of multiple sclerosis.
abstract: OBJECTIVE
  To analyse the safety and effectiveness of natalizumab in the treatment of multiple sclerosis in a real clinical practice setting and according to the approved indications.
  
  
  METHODS
  All patients with multiple sclerosis treated with natalizumab in our centre were evaluated. The clinical and radiological disease activity during the first year of treatment was analyzed in patients who received at least 12 doses of the drug. The data regarding moderate and severe adverse events in the entire study sample was also evaluated.
  
  
  RESULTS
  A total of 112 patients were included in the study, of which 110 had been previously treated with other drugs and 76 had received at least 12 doses of natalizumab. In this group, the annualized relapse rate was reduced by 89% compared to the preceding year and 80% of patients were free from relapses after one year of treatment. Nine percent of patients exhibited 3-month confirmed disability progression. At month 12, the mean number of gadolinium-enhancing lesions on brain MRI was decreased by 99% compared to the pre-treatment MRI. During the first year of treatment, 76% of patients remained free from clinical activity and 33% remained free from both clinical and radiological disease activity. Twenty-nine percent of patients had at least one moderate or severe adverse event, which led to treatment discontinuation in 6%. Four percent of patients experienced immediate hypersensitivity reactions.
  
  
  CONCLUSIONS
  This study suggests that natalizumab is effective in reducing disease activity in patients with relapsing multiple sclerosis and inadequate response to other therapies, with a favorable risk-benefit ratio.
authors.affiliation: Centre d'esclerosi multiple de Catalunya, Barcelona, Espana. ahorga@cem-cat.org
authors.forename: A
authors.initials: A
authors.lastname: Horga
authors.forename: J
authors.initials: J
authors.lastname: Castillo
authors.forename: J
authors.initials: J
authors.lastname: Rio
authors.forename: M
authors.initials: M
authors.lastname: Tintore
authors.forename: C
authors.initials: C
authors.lastname: Auger
authors.forename: J
authors.initials: J
authors.lastname: Sastre-Garriga
authors.forename: M C
authors.initials: MC
authors.lastname: Edo
authors.forename: F
authors.initials: F
authors.lastname: Perez-Miralles
authors.forename: C
authors.initials: C
authors.lastname: Tur
authors.forename: C
authors.initials: C
authors.lastname: Nos
authors.forename: E
authors.initials: E
authors.lastname: Huerga
authors.forename: M
authors.initials: M
authors.lastname: Comabella
authors.forename: A
authors.initials: A
authors.lastname: Rovira
authors.forename: X
authors.initials: X
authors.lastname: Montalban
mesh_terms: D000328:Adult; D000911:Antibodies, Monoclonal / Q000627:therapeutic use*; D061067:Antibodies, Monoclonal, Humanized; D001921:Brain / Q000473:pathology; D018450:Disease Progression; D005260:Female; D006801:Humans; D053208:Kaplan-Meier Estimate; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009103:Multiple Sclerosis / Q000188:drug therapy* / Q000473:pathology / Q000503:physiopathology / Q000517:prevention & control*; D000069442:Natalizumab; D016017:Odds Ratio; D012008:Recurrence; D016896:Treatment Outcome; D055815:Young Adult
chemical_list: D000911:Antibodies, Monoclonal; D061067:Antibodies, Monoclonal, Humanized; D000069442:Natalizumab